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1.
Tissue Barriers ; : 2357406, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38778621

RESUMEN

The blood-testis barrier is a specialized feature within the mammalian testis, located in close proximity to the basement membrane of seminiferous tubules. This barrier serves to divide the seminiferous epithelium into distinct basal and adluminal (apical) compartments. The selectivity of the BTB to foreign particles makes it a safe haven for the virus, and the high affinity of HIV for testis might lead to the vertical transmission of the virus. In the present study, recombinant HIV1-Nef (rNef) protein was injected intravenously to examine the effect of rNef on BTB. SD male rats received 250 µg and 500 µg of rNef along with 2% Evans blue dye within 1 ml through the tail vein. After 1 hour of perfusion, the animals were sacrificed for analysis. The dye migration assay and ELISA confirmed a significant impairment in the blood-testis barrier (BTB) and the manifestation of rNef in testes tissues, respectively. Moreover, a decline in the expression of tight junction proteins, including ZO1 and Occludin, was observed during rNef-induced BTB disruption. Overall, our findings demonstrated that rNef induces BTB disruption through various signaling events. At the site of ectoplasmic specialization of the seminiferous epithelium, the localization of cadherins was found to be disrupted, making the testis a vulnerable site. In conclusion, rNef perturbs the integrity of the blood-testis barrier in rat models; hence, it can also serve as a suitable model for studying the dynamics of the blood-testis barrier.


Established a rodent model to study the integrity of the blood testis barrier (BTB).Recombinant Nef (rNef) of HIV1 can breach the toughest physiological barrier of BTB.Integrity of BTB gets interrupted by rNef through the 'disengagement' and 'engagement' mechanisms of BTB dynamics.Major constituent proteins of BTB, including Occludin and ZO-1 were found to be highly disrupted by rNef; and seem to be the key aberrant for the compromised BTB.rNef also dislocated the localization of N & E cadherins in the rat testes; which would have affected the cadherin-based epithelial adhesion system of BTB and finally caused the breach.

2.
Environ Geochem Health ; 46(2): 65, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38321197

RESUMEN

Rice-based integrated farming system improves the productivity and profitability by recycling resources efficiently. In the sub-humid tropics, rice production without sufficient nutrient replenishment often leads to soil health and fertility degradation. There has been very limited research on soil health and fertility after adopting a multi-enterprising rice-based integrated farming system (IFS), notably in the rice-fish-livestock and agroforestry system, when compared to a conventional farming system (CS). Therefore, the present study analyzed the dynamics of soil properties, soil bacterial community structure and their possible interaction mechanisms, as well as their effect on regulating soil quality and production in IFS, IFSw (water stagnant area of IFS) and CS. The results indicated that soil nutrient dynamics, bacterial diversity indices (Shannon index, Simpson index, Chao 1, ACE and Fisher index) and system productivity were higher in IFSw and IFS compared to CS. Moreover, relative operational taxonomic units of dominant bacterial genera (Chloroflexi, Acidobacteria, Verrucomicrobia, Planctomycetes, Cyanobacteria, Crenarchaeota and Gemmatimonadetes) were also higher in IFSw and IFS compared to CS. Mean soil quality index (SQI) was highest in IFSw (0.780 ± 0.201) followed by IFS (0.770 ± 0.080) and CS (0.595 ± 0.244). Moreover, rice equivalent yields (REY) and rice yields were well correlated with the higher levels of soil biological indices (SQIBiol) in IFS. Overall, our results revealed that rice-based IFS improved the soil health and fertility and ensuing crop productivity through positive interaction with soil bacterial communities and nutrient stoichiometry leading to agroecosystem sustainability.


Asunto(s)
Oryza , Suelo , Suelo/química , Clima Tropical , Agricultura/métodos , Bacterias , Microbiología del Suelo
3.
J Postgrad Med ; 69(3): 146-152, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37313943

RESUMEN

Introduction: Primary open angle glaucoma (POAG) treatment is characterized by long-duration therapy, prescription variability, and non-adherence. Patient awareness toward drug treatment is crucial to ensure adherence. The present study was planned to evaluate drug treatment awareness, patient-perceived drug adherence, and prescription patterns in POAG patients. Methodology: This was a cross-sectional, single-center, questionnaire-based study conducted in the ophthalmology out patient department of a tertiary care hospital from April 2020 to November 2021. Patients of either gender, aged 40-70 years, with a confirmed diagnosis of POAG, who had records of POAG medications for at least last 3 months and who provided written informed consent, were included. Prescription details were recorded, and subsequently, patients were administered a pre-validated drug treatment awareness (14 items) questionnaire, a self-reported medication adherence (9-item) questionnaire, and then they performed eye drop instillation in a simulated setting. Results: The total number of patients enrolled was 180, which yielded 200 prescriptions. The mean drug treatment awareness score was 8.18 ± 3.30, and 135 (75%) patients scored more than 50% (≥7/14). Similarly, 159 patients (83.33%) had scored >50% (i.e. >5/9), with a mean score of 6.30 ± 1.70 in the medication treatment adherence questionnaire. The mean eye drop instillation performance score was 7.18 ± 1.20. The 200 POAG prescriptions containing 306 drugs were analyzed, with beta blockers (184/200, 92%) and timolol (168/200, 84% encounters) being the highest prescribed classes/drugs. Conclusion: POAG patients did have adequate treatment awareness with good self-reported medication adherence and performance of eye drop instillation technique. Around 25% patients lacked awareness; hence, reinforcement education programs on medication regimens need to be implemented.


Asunto(s)
Glaucoma de Ángulo Abierto , Glaucoma , Humanos , Agentes Antiglaucoma , Glaucoma de Ángulo Abierto/tratamiento farmacológico , Estudios Transversales , Glaucoma/tratamiento farmacológico , Cumplimiento de la Medicación , Soluciones Oftálmicas/uso terapéutico , Medición de Resultados Informados por el Paciente
4.
Indian J Pharmacol ; 54(5): 321-328, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36537400

RESUMEN

OBJECTIVE: The rational use of medicines as per the World Health Organization (WHO) should be practiced globally. However, data regarding the completeness of the prescriptions and their rational use is lacking from developing countries like India. Thus, the aim of this study was to assess the prescribing patterns of drugs and completeness of prescriptions as per WHO core drug use and complementary indicators to provide real-life examples for the Indian Council of Medical Research (ICMR) online prescribing skill course for medical graduates. METHODS: Prescriptions of the patients, fulfilling inclusion criteria, attending Outpatient Departments of various specialties of tertiary care hospitals, were collected by thirteen ICMR Rational use of medicines centers located in tertiary care hospitals, throughout India. Prescriptions were evaluated for rational use of medicines according to the WHO guidelines and for appropriateness as per standard treatment guidelines using a common protocol approved by local Ethics committees. RESULTS: Among 4838 prescriptions, an average of about three drugs (3.34) was prescribed to the patients per prescription. Polypharmacy was noted in 83.05% of prescriptions. Generic drugs were prescribed in 47.58% of the prescriptions. Further, antimicrobials were prescribed in 17.63% of the prescriptions and only 4.98% of prescriptions were with injectables. During the prescription evaluation, 38.65% of the prescriptions were incomplete due to multiple omissions such as dose, duration, and formulation. CONCLUSION: Most of the parameters in the present study were out of the range of WHO-recommended prescribing indicators. Therefore, effective intervention program, like training, for the promotion of rational drug use practice was recommended to improve the prescribing pattern of drugs and the quality of prescriptions all over the country.


Asunto(s)
Investigación Biomédica , Farmacología Clínica , Humanos , Prescripciones de Medicamentos , Atención Terciaria de Salud , Pautas de la Práctica en Medicina , Organización Mundial de la Salud
5.
Braz J Biol ; 82: e262815, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35976285

RESUMEN

The objective of the study was to evaluate the quality of Zamzam water, holy water for Muslims and consumed for its medicinal value. The present study demonstrates the physicochemical characterization and wound healing property of Zamzam water. The physicochemical characterization of Zamzam water samples was analyzed for dissolved oxygen, pH, conductivity, total dissolved solids, redox potential, zeta potential, polydispersity index, and zeta size. The microbial quality of Zamzam water was also assessed by exposing water samples to open air. In this work, Zamzam water was also screened for the medicinal value through wound healing properties in Wistar rats. Zamzam water exhibited a unique physicochemical characterization with high levels of dissolved oxygen, zeta potential, polydispersity index, redox potential, total dissolved solids, and conductivity before exposure to open air. After open air exposure, Zamzam water resisted the growth of bacteria. The wound healing properties of Zamzam water in vivo showed a 96% of healing effect on 12th day observation. The wound healing was achieved by modulating pro-inflammatory cytokine such as interleukin -1ß (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor -α (TNF-α). Followed by the level of apoptosis markers caspase-9 and caspase-3 were reduced. The present study proved that Zamzam water is a good-quality water and showed excellent wound healing property. Therefore, Zamzam water can be used for pharmaceutical formulations.


Asunto(s)
Agua , Cicatrización de Heridas , Animales , Oxígeno , Ratas , Ratas Wistar , Factor de Necrosis Tumoral alfa
6.
Diabetes Metab Syndr ; 16(1): 102381, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34995987

RESUMEN

BACKGROUND AND AIMS: We aimed to determine the cause of non-secondary hyperparathyroidism (Non-SHPT) in Indian postmenopausal women. MATERIALS & METHODS: 334 apparently healthy postmenopausal women were assessed for bone mineral homeostaisis including Vitamin D, PTH and VDR polymorphism. RESULTS: 83% of the subjects had vitamin D deficiency further associated with VDR gene polymorphism (P 0.000). A sizable number of subjects (N = 83) did evoke SHPT despite low vitamin D levels. We observe that VDR gene polymorphism was strongly associated in the sub-group of non-SHPT. CONCLUSION: lack of SHPT warrants researchers to study the pathophysiology of non-SHPT in detail to substantiate our findings.


Asunto(s)
Hiperparatiroidismo Secundario , Deficiencia de Vitamina D , Femenino , Humanos , Hiperparatiroidismo Secundario/genética , Hormona Paratiroidea , Polimorfismo Genético , Posmenopausia , Receptores de Calcitriol/genética , Vitamina D , Deficiencia de Vitamina D/complicaciones , Deficiencia de Vitamina D/genética
7.
J Anal Test ; 5(4): 327-340, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34777896

RESUMEN

The COVID-19 outbreak led to an uncontrollable situation and was later declared a global pandemic. RT-PCR is one of the reliable methods for the detection of COVID-19, but it requires transporting samples to sophisticated laboratories and takes a significant amount of time to amplify the viral genome. Therefore, there is an urgent need for a large-scale, rapid, specific, and portable detection kit. Nowadays nanomaterials-based detection technology has been developed and it showed advancement over the conventional methods in selectivity and sensitivity. This review aims at summarising some of the most promising nanomaterial-based sensing technologies for detecting SARS-CoV-2. Nanomaterials possess unique physical, chemical, electrical and optical properties, which can be exploited for the application in biosensors. Furthermore, nanomaterials work on the same scale as biological processes and can be easily functionalized with substrates of interest. These devices do not require extraordinary sophistication and are suitable for use by common individuals without high-tech laboratories. Electrochemical and colorimetric methods similar to glucometer and pregnancy test kits are discussed and reviewed as potential diagnostic devices for COVID-19. Other devices working on the principle of immune response and microarrays are also discussed as possible candidates. Nanomaterials such as metal nanoparticles, graphene, quantum dots, and CNTs enhance the limit of detection and accuracy of the biosensors to give spontaneous results. The challenges of industrial-scale production of these devices are also discussed. If mass production is successfully developed, these sensors can ramp up the testing to provide the accurate number of people affected by the virus, which is extremely critical in today's scenario.

8.
PLoS One ; 16(10): e0258166, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34606515

RESUMEN

Understanding the spatial spreading patterns of plant-available sulphur (S) (AS) and plant-available micronutrients (available zinc (AZn), available iron (AFe), available copper (ACu), available manganese (AMn) and available boron (AB)) in soils, especially in coastal agricultural soils subjected to various natural and anthropogenic activities, is vital for sustainable crop production by adopting site-specific nutrient management (SSNM) strategies. We studied the spatial distribution patterns of AS, AZn, AFe, ACu, AMn, and AB in cultivated soils of coastal districts of India using geostatistical approaches. Altogether 39,097 soil samples from surface (0 to 15 cm depth) layers were gathered from farm lands of 68 coastal districts. The analysis of soil samples was carried out for soil pH, electrical conductivity (EC), soil organic carbon (SOC) and AS, AZn, AFe, ACu, AMn, and AB. Soil pH, EC and SOC varied from 3.70 to 9.90, 0.01 to 7.45 dS m-1 and 0.02 to 3.74%, respectively. The concentrations of AS, AZn, AFe, ACu, AMn, and AB varied widely in the study area with their corresponding mean values were 37.4±29.4, 1.50±1.53, 27.9±35.1, 2.14±1.74, 16.9±18.4 and 1.34±1.52 mg kg-1, respectively. The coefficient of variation values of analyzed soil parameters varied from 14.6 to 126%. The concentrations of AS, AZn, AFe, ACu, AMn, and AB were negatively and significantly correlated with soil pH and positively and significantly correlated with SOC. The geostatistical analysis indicated stable, Gaussian and exponential best-fit semivariogram models with moderate to strong spatial dependence for available nutrients. The generated spatial spreading maps revealed different distribution patterns for AS, AZn, AFe, ACu, AMn, and AB. There were variations in spatial spreading patterns of AS, AZn, AFe, ACu, AMn, and AB in east- and west-coastal area. About 62, 35, 12, 0.4, 23 and 45% of the study area had deficiency of AS, AZn, AFe, ACu, AMn, and AB, respectively. The spatial spreading maps will be highly useful for SSNM in the cultivated coastal soils of the country. This study could also be used as a base for assessing spatial spreading patterns of soil parameters in cultivated coastal areas of other parts of the world.


Asunto(s)
Micronutrientes/análisis , Suelo/química , Azufre/análisis , Agricultura , Geografía , India , Estadística como Asunto
9.
Int J Appl Comput Math ; 7(3): 77, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33937442

RESUMEN

Growing business process and rising aggressive conditions are encouraged to use the inventory control scheme and components in an ideal way. Cash discount and permissible delay are beneficial for vendor and buyer both. This study considers an EOQ model through demand rate depends on the time. A lower or higher time leads to lower or higher demand after feedback vice versa. In this paper deterioration, cash- discount, shortages and permissible delay are also considered. Mathematical models are discussed under four different states of affair. Solution method is given for finding the finest answer. The main aim is to maximize total profit. Numerical examples are provided for all four dissimilar situations. Optimal values with strictures are calculated to analyze the sensitivity investigation of optimal strategy concerning the parameters of the system. It is revealed that the total income is concave by means of cycle time.

10.
Indian J Hematol Blood Transfus ; 37(2): 210-219, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33867726

RESUMEN

Aplastic anemia (AA) is an immune-mediated disorder in which hematopoietic stem and progenitor cells are targeted by a number of cellular and molecular pathways. This case control study aims to investigate the association of interleukin-1beta (IL-1ß) gene polymorphisms, (IL-1ß-31, IL-1ß-511 and IL-1ß-3954) and their plasma levels with acquired AA. Genotyping was done by Restricted Fragment Length Polymorphism (PCR-RFLP) method and IL-1ß plasma levels were evaluated in peripheral blood using ELISA. Increased level of IL-1ß was reported to be significant in cases as compared to controls. The susceptibility of developing AA was higher in the cases for IL-1ß-3954 genotype. IL-1ß-511 genotype showed significant association with the severity groups of AA. No significant association was noticed in responder versus non-responder group. Plasma level of IL-1ß gene was found to be significantly higher in severe and very-severe group of AA versus control group. Our findings suggest that IL-1ß gene and its genotypes might be involved in the pathophysiology of AA and play a central role in the etiopathogenesis of AA.

11.
PLoS One ; 15(6): e0234053, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32484834

RESUMEN

The efficient (site-specific) management of soil nutrients is possible by understanding the spatial variability in distribution of phyto-available nutrients (here after called available nutrients) and identifying the soil management zones (MZs) of agricultural landscapes. There is need for delineating soil MZs of agricultural landscapes of the world for efficient management of soil nutrients in order to obtain sustainability in crop yield. The present study was, therefore, undertaken to understand the spatial distribution pattern of available micronutrients (zinc (Zn), boron (B), iron (Fe), manganese (Mn) and copper (Cu)), available sulphur (S), and soil properties (soil acidity (pH), electrical conductivity (EC) and organic carbon (SOC) content) in soils of intensively cultivated Indo-Gangetic Plain (IGP) of India and to delineate soil MZs for efficient management of soil nutrients. Totally, 55101 soil samples from 0-15 cm depth were obtained from 167 districts of IGP during 2014 to 2017 and were analysed for different soil parameters. Soil pH, EC and SOC content varied from 4.44 to 9.80, 0.02 to 2.13 dS m-1 and 0.10 to 1.99%, respectively. The concentration of available Zn, B, Fe, Mn, Cu and S varied from 0.01 to 3.27, 0.01 to 3.51, 0.19 to 55.7, 0.05 to 49.0, 0.01 to 5.29 and 1.01 to 108 mg kg-1, respectively. Geostatistical analysis resulted in varied distribution pattern of studied soil parameters with moderate to strong spatial dependence. The extent (% area) of nutrient deficiencies in IGP followed the order: S > Zn > B > Mn > Cu > Fe. Principal component analysis and fuzzy c-means clustering produced six distinctly different soil MZs of IGP for implementation of zone-specific soil nutrient management strategies for attaining sustainability in crop yield. The developed MZ maps could also be utilized for prioritization and rationalization of nutrients supply in IGP of India.


Asunto(s)
Monitoreo del Ambiente , Micronutrientes/análisis , Suelo/química , Análisis Espacial , Azufre/análisis , India , Lluvia , Estadística como Asunto
12.
Sci Rep ; 10(1): 640, 2020 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-31959919

RESUMEN

Hexavalent chromium is extremely toxic and increasingly prevalent owing to industrialisation, thereby posing serious human health and environmental risks. Therefore, new approaches for detoxifying high concentrations of Cr (VI) using an ultralow amount of catalyst with high recyclability are increasingly being considered. The catalytic conversion of Cr (VI) into Cr (III) was previously reported; however, it required a large amount of catalyst to reduce a low concentration of Cr (VI); further, pH adjustment and catalyst separation had to be performed, causing issues with large-scale remediation. In this study, an unprecedented eco-friendly and cost-effective method was developed for the synthesis of Pd nanoparticles (PdNPs) with a significantly narrow size distribution of 3-25 nm. PdNPs demonstrated the presence of elemental Pd with the zero oxidation state when analysed by energy-dispersive X-ray analysis and X-ray photoelectron spectroscopy. The PdNPs could detoxify a high concentration of Cr (VI), without the need to adjust the pH or purify the nanoparticles for reusability. The reusability of the PdNPs for the catalytic conversion of Cr (VI) into Cr (III) was >90% for subsequent cycles without the further addition of formic acid. Thus, the study provides new insights into the catalytic reclamation of Cr (VI) for industrial wastewater treatment.

13.
J Postgrad Med ; 66(1): 28-34, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31898596

RESUMEN

Patients often approach a pharmacist instead of visiting a doctor for minor ailments such as cough, cold, allergies, pain, fever, acidity, diarrhea, and skin-related conditions. Purchase of specific medicines over the counter is legally recognized in most countries. 'Over-the-Counter (OTC) Medicines' means drugs which are legally allowed to be sold by pharmacists without need for a prescription. The term does not have a legal definition in India. Technically, drugs are OTC unless they are specifically stated as prescription only drugs. OTC drugs allow faster and cheaper access to healthcare; however, their misuse and adverse health effects cause concerns. This article describes concept of OTC medicines and practices in India against the background of globally prevalent regulations and practices. A recognized category of OTC medicines by law, patient awareness programs, and support of pharmacists and pharmaceutical companies are required to optimize the use of OTC medicines in India.


Asunto(s)
Medicamentos sin Prescripción , Farmacéuticos , Automedicación , Conocimientos, Actitudes y Práctica en Salud , Humanos , India , Rol Profesional , Salud Pública , Automedicación/efectos adversos
14.
Nanomaterials (Basel) ; 9(12)2019 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-31842495

RESUMEN

Comprehension of the shape-dependent properties of gold nanoparticles (AuNPs) could benefit the advancements in cellular uptake efficiency. Spherical AuNPs have generally been used for drug delivery, and recent research has indicated that the cellular uptake of triangular AuNPs was higher than that of spherical ones. Previous reports have also revealed that chemically synthesized AuNPs were cytotoxic. Therefore, we have developed a facile, cost-effective, and environmentally friendly method for synthesizing triangular and hexagonal anionic AuNPs. The zeta potential of the synthesized AuNPs was negative, which indicated that their surface could be easily functionalized with positively charged molecules to upload drugs or biomolecules. Transmission electron microscopy (TEM) images illustrated that the largest particle size of the synthesized quasi-hexagonal AuNPs was 61 nm. The TEM images also illustrated that two types of equilateral-triangular AuNPs were synthesized: One featured sharp and the other rounded corners. The sides of the smallest and largest triangular AuNPs were 23 and 178 nm, respectively. Energy-dispersive X-ray spectra of the green-synthesized AuNPs indicated that they consisted entirely of elemental Au. The cytotoxicity of the green-synthesized AuNPs was evaluated using 3T3-L1 adipocytes. Using cell viability data, we determined that the green-synthesized AuNPs did not exhibit any cytotoxic effects on 3T3-L1 adipocytes.

16.
Environ Geochem Health ; 41(5): 1923-1937, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30719612

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) and potentially toxic elements (PTEs) (Ba, Zn, Pb, Cu, Cr, Ni, As, Co) were determined in the road dusts of a coal mining area (Dhanbad, India) to assess their content and potential human health risks. Dust samples were collected from sign boards of the heavy traffic road connecting Dhanbad and Sindri. The total PAHs (∑PAHs, all values in mg/kg) content in the road dust samples varied from 3.98 to 13.1, with carcinogenic PAHs content of 14.8-34.4% of the ∑PAHs. Phenanthrene (2.72), fluorene (0.715) and pyrene (0.575) are the major PAHs. Principal component analysis revealed that these PAHs are probably originated from pyrogenic (coal combustion and traffic emission) and petrogenic (coal dust, tyre and road particles) sources. Among the PTEs, the mean content was higher for Ba (293 mg/kg) followed by Zn (224), Pb (128), Cu (52.6), Cr (45.2), Ni (22.0), As (17.5) and Co (8.11). The overall pollution load index varied from 0.43 to 1.0. Source analysis showed that PTEs in the road dust of the study site were derived from traffic emission (Zn, Fe, Mn, Co and Pb), coal dust (Cr, As and Ni) and soil (K, Mg, Ba, Sr and Ca). In general, the PTEs are lower, but the PAHs contents were elevated in the road dust samples. Although the exposure risks from PTEs are low, the risk to children (expressed as hazardous quotient) for As and Pb is near to the permissible limit of 1.0. Cancer risk from PAHs for adult (4.8 × 10-6) and child (5.3 × 10-6) has exceeded the acceptable limit of 10-6.


Asunto(s)
Minas de Carbón , Polvo/análisis , Exposición a Riesgos Ambientales/análisis , Contaminantes Ambientales/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Carcinógenos/análisis , Carbón Mineral/análisis , Monitoreo del Ambiente , Humanos , India , Medición de Riesgo
17.
Sci Total Environ ; 665: 890-912, 2019 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-30790762

RESUMEN

This review covers the current and emerging analytical methods used in laboratory, field, landscape and regional contexts for measuring soil organic carbon (SOC) sequestration in agricultural soil. Soil depth plays an important role in estimating SOC sequestration. Selecting appropriate sampling design, depth of soil, use of proper analytical methods and base line selection are prerequisites for estimating accurately the soil carbon stocks. Traditional methods of wet digestion and dry combustion (DC) are extensively used for routine laboratory analysis; the latter is considered to be the "gold standard" and superior to the former for routine laboratory analysis. Recent spectroscopic techniques can measure SOC stocks in laboratory and in-situ even up to a deeper depth. Aerial spectroscopy using multispectral and/or hyperspectral sensors located on aircraft, unmanned aerial vehicles (UAVs) or satellite platforms can measure surface soil organic carbon. Although these techniques' current precision is low, the next generation hyperspectral sensor with improved signal noise ratio will further improve the accuracy of prediction. At the ecosystem level, carbon balance can be estimated directly using the eddy-covariance approach and indirectly by employing agricultural life cycle analysis (LCA). These methods have tremendous potential for estimating SOC. Irrespective of old or new approaches, depending on the resources and research needed, they occupy a unique place in soil carbon and climate research. This paper highlights the overview, potential limitations of various scale-dependent techniques for measuring SOC sequestration in agricultural soil.

18.
Int J Biometeorol ; 63(3): 337-349, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30680629

RESUMEN

Photosynthetically active radiation (PAR) is one of the most important environmental factors that determine the productivity and grain quality of the crops. Continuous rainy days or cloudy weather throughout crop growth especially at critical stages often resulted in great loss of grain quality and yield in rice. Low light stress has rigorously constrained the rice production in various rice-growing regions, especially in Southeast Asia. Method and time of planting are the major management factors contributing to the higher yield potential of rice by influencing light harvesting and use efficiency. Present study was executed consecutively for 5 years (kharif seasons of 2012-2016) to determine whether planting time improves the radiation absorption and use efficiency in different duration rice cultivars. We evaluated the difference in plant growth and development leading to yield formation under different planting time which related to radiation incidence and interception. The results of the study revealed that PAR interception depends on morphological characters of cultivars and also with agronomic management such as transplanting time and method. Long duration cultivar intercepted more PAR but interception decreased due to late planting (3rd week of July), whereas short duration cultivars (Naveen) when planted earlier (1st week of June) could not effectively utilize intercepted PAR constraining the biomass accumulation and yield formation. Effect of planting density and crop architecture on PAR absorption was apparent among establishment methods as light interception at crop canopy was highest in the system of rice intensification and lowest in that of wet direct seeding. In general, Pooja as a long duration cultivar intercepted more PAR per day but when compared on same date of planting, the comparative absorption of radiation was 30.6% higher in Naveen. The lower yields in the wet season are attributed mostly to reduction in grain number per panicle or per unit land area, which is a consequence of high spikelet sterility. Grain yield of rice planted in July third week was reduced by 3.8, 12.3, and 6.9% over June first and third week and July first week, respectively, mainly due to spikelet sterility (26%) and lower grains per panicle (18%). Our results indicated that agronomic management like optimum time of sowing, cultivar duration, and establishment methods should be followed for yield improvement in tropical lowlands where light intensity is limiting due to prevailing weather situations.


Asunto(s)
Agricultura/métodos , Oryza/crecimiento & desarrollo , Luz Solar , Hojas de la Planta/crecimiento & desarrollo , Estaciones del Año , Temperatura
20.
J Microbiol Methods ; 157: 65-80, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30552971

RESUMEN

The biosynthesis of nanomaterials is a huge and intensifying field of research due to their application in various areas, in particular the biomedical and pharmaceutical fields. In this review, we focused on the biosynthesis of both metallic and semiconductor nanomaterials and their application in biomedicine and pharmaceutics. In order to meet an exponentially increasing need for nanostructured materials, the biological route for the synthesis of nanomaterials will have to be explored, offering advantages over chemical and physical methods as a simpler, more cost effective, and environmentally friendly method, and for which there is no need to use high pressure and temperatures or toxic chemicals. This review discusses in detail the potential role of bioreducing and capping/stabilizing agents in biosynthesis. This review also investigates the application of various biosynthetic nanomaterials as antimicrobial materials, in clinical detection, for drug delivery and wound-healing, and as anti-diabetic materials.


Asunto(s)
Bacterias/metabolismo , Reactores Biológicos/microbiología , Vías Biosintéticas/fisiología , Hongos/metabolismo , Nanopartículas del Metal/química , Antiinfecciosos , Sistemas de Liberación de Medicamentos , Semiconductores , Cicatrización de Heridas
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